Many people experience breathing problems on a recurring basis, which often result in sleep disordered breathing (i.e., difficulty sleeping, snoring, or other more serious conditions such as obstructive sleep apnea). Previous devices for improving a user's breathing have included face masks, nose masks, or nasal inserts that help deliver air to the user's nose at positive pressure. These devices help force open the user's breathing passage and thereby improve the user's breathing. However, previous devices have often provided an inadequate fit, been unstable, and been prone to movement when users are sleeping, and have often required multiple straps or other devices to hold them in place. Thus, previous devices have caused discomfort for users and have often failed to adequately prevent leakage.